Thermal transport properties in helium near the superfluid transition. III. Dilute /sup 3/He-/sup 4/He mixtures in the normal phase

Journal Article · Wed Jul 01 04:00:00 EDT 1987 · J. Low Temp. Phys.; (United States)

DOI:https://doi.org/10.1007/BF00682622· OSTI ID:6060523

Zhong, F; Gestrich, D; Dingus, M; Meyer, H

An experimental study is presented for the thermal conductivity kappa and the thermal relaxation for dilute mixtures of /sup 3/He in /sup 4/He with concentration 9 x 10/sup -4/ less than or equal to X(/sup 3/He) less than or equal to 5 x 10/sup -2/ at saturated vapor pressure and in the normal phase near the superfluid transition. The conductivity results for kappa are compared with predictions by Dohm and Folk from field-theoretic renormalization group (RG) theory. The conductivity kappa/sub s/ = (kappa/sup -1/ (t) - kappa/sup -1/ (T/sub lambda/))/sup -1/, is compared with Ahlers' phenomenological arguments, and also with predictions by Dohm and Folk and by Onuki. The temperature difference transient ..delta..T(t) across the fluid, measured as a function of time t after switching on and off the heat current is analyzed. The thermal diffusion ratio k/sub T/ and the mass diffusion coefficient D are obtained by fitting the calculated transient to the experimental one. The results are compared with the predictions that follow from the RG approach by Dohm and Folk. Very good agreement is obtained for k/sub T/. The transient is not very sensitive to D, and hence the determination is not accurate. Yet within the uncertainty, the deduced D also agrees with predictions. Appendices give (1) the corrections to kappa from finite heat effects, (2) the calculation of the concentration susceptibility (deltaX/delta..delta..)/sub T,P/, and (3) the calculation procedure for kappa, k/sub T/, and D using the RG approach of Dohm and Folk.

• Research Organization: Duke Univ., Durham, NC
• OSTI ID: 6060523
• Journal Information: J. Low Temp. Phys.; (United States), Journal Name: J. Low Temp. Phys.; (United States) Vol. 68:1-2; ISSN JLTPA
• Country of Publication: United States
• Language: English

Related Subjects

640450* -- Fluid Physics-- Superfluidity
75 CONDENSED MATTER PHYSICS
SUPERCONDUCTIVITY AND SUPERFLUIDITY
BINARY MIXTURES
COUPLING
DIFFUSION
DILUTION
DISPERSIONS
ENERGY TRANSFER
ENTROPY
EVEN-EVEN NUCLEI
EVEN-ODD NUCLEI
FLUID MECHANICS
GROUP THEORY
HEAT TRANSFER
HELIUM 3
HELIUM 4
HELIUM ISOTOPES
HYDRODYNAMICS
INTERMEDIATE COUPLING
ISOTOPES
J-J COUPLING
LIGHT NUCLEI
MAGNETIC PROPERTIES
MAGNETIC SUSCEPTIBILITY
MATHEMATICAL MODELS
MATHEMATICS
MECHANICS
MIXTURES
NUCLEI
PHYSICAL PROPERTIES
RELAXATION TIME
RENORMALIZATION
STABLE ISOTOPES
SUPERFLUIDITY
TEMPERATURE GRADIENTS
TEMPERATURE MEASUREMENT
THERMAL CONDUCTIVITY
THERMAL DIFFUSION
THERMAL DIFFUSIVITY
THERMODYNAMIC PROPERTIES
TIME DEPENDENCE
ULTRALOW TEMPERATURE